textproduct: Rapid City

KEY MESSAGES

- Light precipitation possible through tonight.

- Moderate to heavy snowfall expected for much of the area Saturday into Sunday.

- Warm and mostly dry conditions return for next week.

UPDATE

Issued at 936 PM MDT Fri Mar 13 2026

Stalled frontal boundary across the region continues to support an FGEN band across NW SD with light snow ongoing there. Upslope fog is in place along the northern and eastern foothills. LL winds are expected to respond to the approaching upper trough, veering SE. This should support improvement of fog later tonight as dry air moves back into the area. Sfc front will shift back north Sat, with warm mild area spreading across the far southern FA, where 50s and 60s are expected. Light snow will continue across far NW SD through much of Sat, with temps expected to remain below freezing. Expect 1-2 inches of accums tonight through Sat there. Cold front still expected to move into the region Sat afternoon. Hires models are indicating a potential snow squall setup as a dynamically driven band of precip is depicted advecting across the area. Steep LL lapse rates and strong CAA indicated along the front, with ample post frontal moisture, all good ingredients for this. If a band of snow does materialize, expect a quick 1-2 inches given convective component. Perhaps the only change from the previous forecast is a downward trend in snow amounts across much of the area. Main band of snow will develop east of the FA Sat night with generally light to moderate snow here. Although snow amounts look less, still expecting an impactful storm locally given strong northerly winds gusting over 50 mph, which will support ample blowing/drifting snow and whiteout conds at times on parts of the SD Plains. Still expecting upslope snow in the northern BH and foothills, which could certainly support decent localized amounts there. Things dry out Sunday, with very cold conds Sunday night as lows drop into the single digits at many locations. Warming up next week with mainly dry weather after a warm front moves through Monday at which time some light precip will be possible

DISCUSSION

(This Evening Through Friday) Issued at 117 PM MDT Fri Mar 13 2026

Northwest upper flow continues over the forecast area today, as mild troughing sits over the Great Lakes region. Surface analysis shows warm frontal boundary running from northeastern WY down into southwestern SD this afternoon. North of the warm front, radar shows light precipitation ongoing from northwest down into south central SD. Winds are relatively light this afternoon with temperatures in the 30s to upper 40s.

Mid-level forcing will continue to bring areas of light precipitation over the region through tonight. Best chance for light accumulations are expected over northwestern SD. Upper trough thats currently sitting over the PAC NW coast will traverse southeast the rest of today, moving into the northern plains on Saturday. Strong forcing associated with this wave will bring moderate to heavy precipitation into the forecast area starting late Saturday morning in northwestern SD and over spreading the region throughout the day. Baroclinic zone is expected over the FA, and will result in some areas in the southern half of the area seeing rain to start or a rain/snow mix, before transitioning. Associated cold front with this system will move south throughout the day, bringing arctic air behind it. Frontogenesis banding is expected Saturday evening into Sunday morning. Currently models differ a bit on where the heavier banding will set up, but overall consensus points to northwestern into northern SD, where 4-8 inches of snowfall will be possible between Saturday afternoon and Sunday morning. Have issued a Winter Storm Warning covering northwestern SD as well as the northern and Wyoming Black Hills where upslope enhancement is expected to bring 6-10 inches in the higher elevation areas. Further south, a bit lighter snowfall accumulations are expected closer to I-90, however strong winds will accompany the snowfall behind the front. Have issued a Winter Storm Advisory for areas along I-90 east of the Black hills into south central SD, as well as parts of the northeastern WY plains counties. These areas can expect generally 2-5 inches of snow, but stronger wind gusts up to 40-50 mph behind the cold front. Precipitation will taper off from west to east Sunday morning into the afternoon, however gusty winds may linger a bit into the early evening hours.

Looking ahead into next week, following this winter system upper ridging builds over the western CONUS Sunday night and sticks around for much of next week. This will result in mostly dry conditions and a warming trend. Highs by Tuesday bounce back into the mid 50s and 60s, and longer range models point to potential for record breaking highs later in the work week. Thursday and Friday look to be the warmest days, where highs could even reach into the 80s for some areas.

AVIATION

(For the 12Z TAFS Through 12Z Sunday Morning) Issued At 439 AM MDT Sat Mar 14 2026

Widespread MVFR/IFR conditions in low clouds and areas of light snow will persist today across much of northeastern WY into the northern Black Hills. VFR conditions are expected elsewhere.

A strong cold front will cross the area late this afternoon into the evening. This will bring gusty northwest winds, widespread snow, and blowing snow. Flight conditions will reduce to MVFR to IFR (CIGS & VSBY) behind the front and continue through the rest of the forecast period.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Winter Storm Warning from noon today to noon MDT Sunday for SDZ001-002-078. Winter Storm Warning from 6 PM this evening to noon MDT Sunday for SDZ012>014-024-025-032-072-073. Winter Weather Advisory from 6 PM this evening to noon MDT Sunday for SDZ026-030-031-042-076. Winter Weather Advisory from 9 PM MDT /10 PM CDT/ this evening to noon MDT /1 PM CDT/ Sunday for SDZ043-044-046-047-049- 077. WY...Winter Storm Warning from 6 PM this evening to noon MDT Sunday for WYZ057-060. Winter Weather Advisory from 6 PM this evening to noon MDT Sunday for WYZ054>056.